120 SAN DIEGO SOCIETY OF NATURAL HISTORY 
WALCOTT (Charles D.)—Continued 
The following species are referred to the genus: Callavia bicensis Walc., C. brog- 
geri Walc., C. burri Wale. C. callavei Lapw., C. cortlandi Raw. Mss., C. crosbyi 
Walc. and C. nevadensis Walc. 
Holmia Matthew genotype Paradoxides Kyerulfi Linnarsson, 1871. 
The species referred to Holmia are H. kjerulf, H. lundgreni and H. rowei Walc., 
the only American species. : 
Wanneria new genus. Genotype W. Walcottanus Wanner. 
This genus has a uniform series of thoracic segments, with pleurae terminating in 
broad faleate extensions beyond the body line, without the spinose ends as in Holmia. 
The species referred to Wanneria are: W. Walcottanus Wanner, IW’. gracile Wale. 
and W. Halli Walcott. 
Paedeumias n. gen. Genotype P. transitans Walcott. 
The distinctive characters of the genus are in the presence of the rudimentary seg- 
ments and pygidium. 
Olenellus Hall. Genotype O. Thompsoni Hall. 
The author remarks that Olenelius Thompsoni passes through a Holmia-and Paedeu- 
mias stage before becoming a trve Olenellus. 
The American species are Olenellus Thompsoni Hall and variety O. crassimarginatus 
Walcott, O. gilberti Meek, O. fremonti Walc., O. canadensis Wale., O. claytoni Walc., 
O. argentus Walc., O. walcotti §. & F. 
The European species are O. gigas Peach, O. lapaorthi Peach, O, reticulatus Peach 
and Olenellus n. sp. undt. 
All these species have telsonated pygidia and may be classed under the family name 
of Olenellidae. 
Peachella new genus. Genotype P. iddingsi Walcott. 
The genus is only known by the head, which has blunt, tumid genal spines; elon- 
gated, narrow glabella; smal! eyes and marked convexity. 
Olenelloides Peach. Genotype O. armatus Peach. 
This genus is clearly defined by its large cephalon and primitive thorax and_ py- 
gidium. The author remarks it is essentially a larval form of Olenellus, The author 
diagrammatically represents these Lower Cambrian genera under the family of Meson- 
cidae. Left-hand branch Nevadia, Callavia, Holmia, Wanneria,—Paradoxides, Right- 
hand branch Nevadia, Mesonacis, Elliptocephala, Paedeumias, Olenellus, Peachella— 
Ollenoides. 
——— Cambrian Geology and Paleontology, No. 7. Cambro-Ordo- 
vician boundary in British Columbia, with deseription of Fossils, 
Smithsonian Mis. Coll., vol. 57, No. 7, 1912. 
The author describes Certopyge canadensis n. sp. 
This species differs from C. forficula Sars in the greater length of the frontal limb 
te. 
@ 
of the cranidium, longer palebral lobes and narrower fixed cheeks, 
a Cambrian Geology and Palwontology—2, No. 6. Middle Cam- 
brian Brachiopoda, Malacostraca Trilobita and Merostoma, with plates 
24 to 34. 
Smithsonian Misc. Coll., vol. 57, No. 6, 1912. 
Under the class Malacostraca, the author describes the following species: 
Hymenoceris circularis n. sp., H. obliqua n. sp. H. ovalis n. sp., H. parva n. spy 
H. perfecta n. sp., H. vermicauda., 
Trilobita: Neolenus serratus Rominger. Ptychoparia cordillerae Rominger. Mar- 
rella n. gen., M. spendens n. sp. 
